Bags and carrying cases are commonly used to transport items from one location to another. Items may be contained and supported within an internal enclosure during transportation. Most bags also include some form of user attachment system that allows a user to support the bag during transportation. Many types of user attachment systems are designed to be positioned on a user's body in a configuration that supports the bag but does not require the use of appendages. For example, backpack shoulder straps may be individually looped around each of a user's shoulders to support the backpack in an orientation that does not require the user to hold it with their arms. However, each type of user-attachment system possesses particular performance characteristics and limitations that affect the utility of the bag. For example, a single shoulder strap or messenger-style user attachment system is undesirable for exclusive support of a bag with heavier loads due to potential back and/or shoulder discomfort.
Bags and carrying cases may be further classified according to their overall shape, user-attachment system(s), and material of composition. One subset of carrying cases includes bags which attach to a user's waist, including backpacks, hip-packs, shoulder bags, messenger bags, etc. These types of carrying systems may also include other user-attachment systems in addition to a waist attachment such as shoulder straps, handles, etc. A waist attachment system refers to some form of straps, belts, hooks, etc. that couple to the waist region of a user. In general, the carrying portion of the carrying system is primarily positioned on the dorsal side of the user, and the waist attachment system includes two straps which extend from the left and right sides respectively to the ventral side of the user's body. The two straps may then be releasably coupled together so as to form a singular support strap encircling the user's dorsal and ventral waist region from the carrying portion of the carrying system. By encircling the user's waist with support straps, weight is distributed between the carrying portion of the carrying system and the user's waist”.
One of the problems with existing waist-type user attachment systems is the inability of the waist attachment system to efficiently articulate in accordance with the movement of the user. When a user walks or runs, each hip sequentially rises and falls within the coronal plane a small amount corresponding to the leading leg/foot in order to allow the hip joint to properly articulate. Conventional hip attachment systems are rigid in that they directly transfer all user hip movement to the carrying portion and therefore require synchronization of hip and carrying portion movements. For example, if one hip is raised, the corresponding side of the carrying portion must also be raised. Unfortunately, this synchronization of movements causes the user to perform unnecessary work as a result of repeatedly raising the weight of the carrying portion with each stride. In addition, a user generally leans forward in the sagittal plane while walking uphill, and the dorsal hip region intermittently tilts slightly forward in the sagittal plane during movement. The necessary synchronization of hip and carrying portion movements thereby causes the carrying portion to be raised and lowered as a result of the sagittal movement. Over long distances and higher pack weights, the required synchronization of hip and carrying portion movements significantly increases the workload of the user.
Some of these problems have been overcome by existing hip attachments systems, but each respective system has failed to efficiently provide optimal articulation without introducing additional problems. For example, merely allowing the hip attachment point to freely rotate coronally will result in undesirable weight distribution at particular lateral lean angles. In addition, many of the existing articulating hip attachment systems require elimination of existing adjustability functions such as a torso length adjustment.
Therefore, there is a need in the industry for an improved carrying system hip-type user attachment system that provides the optimal articulation characteristics while maintaining existing adjustment and comfort parameters.